Yes, I can reproduce it.
It looks like this code is too low on the page:
<script src="webassist/jq_validation/jquery.h5validate.js"></script>
I'm not sure if it is coming in from a plugin or on the page itself, but it has to be above the payment form and it is currently below. Its exact position has to be after the jquery library, but before any references to h5validate on the page....
Another option would be to move the payment scripts lower on the page... either that script has to move up or the script that refers to it has to move down.
If you give me FTP access I can correct it.